Do you feel like youre riding a premenstrual roller coaster every month that leaves you feeling hungry, tired, angry, sad, and unsexy?

Leading researcher and womens hormone expert Dr. Sarah E. Hill explains why we feel so universally icky before our periods and what to do about it.The problem isnt that women are hormonal; the problem is that the second half of the menstrual cyclethe luteal phase, when the hormone progesterone rises and estrogen decreaseshas been systematically ignored by science and medicine.

Progesterone is at the heart of every feeling we associate with PMS: it affects our daily sleep and calorie needs (hello, cravings!); whom were attracted to; our sex drive; andas every woman can attestour mood. Because the luteal phase is understudied, every bit of health, diet, and relationship advice youve followed is based on that first, estrogen-glow half of the month or, worse, was designed for men.

The rules that work for us in the first two weeks of the cycle dont always fit in the second, causing most of us to spend half the month following advice that is completely at odds with the way our bodies work at this time. Its no wonder we feel awful!Dr. Hill demystifies how our bodies work, so you can work with your hormones to:

Sidestep PMS cravings by eating more you burn up to 11% extra calories in the luteal phase!

Exercise in a way thats invigorating instead of draining.

Understand your sex drive, and why sex has different meaning across the month.

Quit bad habits more easily thanks to progesterones addiction-busting properties.

Navigate motivational and energy dips without added stress.

Incorporate anti-inflammatory foods and habits to naturally ease PMS.

The Period Brain is a science-tested roadmap to understanding PMS and PMDD. Its time we demand a better month, every month and usher in a new era in womens health. Period.